The BBSP Deadline Passed. Now What? A Guide for Local Officials

The BBSP Deadline Passed. Now What? A Guide for Local Officials

By EditorJul 18, 20260 Comments
The Block Boundary Suggestion Project (BBSP) exists so that states can identify non-standard features often used as electoral boundaries (power lines, property lines, or streams) that could serve alongside more traditional features (such as street centerlines) as census tabulation block boundaries. States, through their official liaisons, may also identify features that are not desirable as block boundaries. In addition, legal boundaries reviewed in coordination with the annual Boundary and Annexation Survey also become census tabulation block boundaries. Where no suggestions are submitted, local precinct boundaries following features the Bureau does not already carry are unlikely to appear as census block…
DATA and TECHNOLOGY, Local Redistricting, , ,
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The Boundary Annexation Survey (BAS) Submission Checklist for Local Governments

The Boundary Annexation Survey (BAS) Submission Checklist for Local Governments

By EditorJul 14, 20260 Comments
The Boundary and Annexation Survey (BAS) is the Census Bureau's annual check-in with local government on where its legal boundaries actually are. Each year the Bureau contacts federally recognized American Indian areas, counties and county equivalents, incorporated places, and minor civil divisions, asking each to confirm that the Bureau has the correct boundary, name, and status for that government. The public and data users rely on the annual BAS boundaries as the official federal representation of boundaries for legal governments. The Census Bureau maintains this data in its MAF/TIGER System and publishes the results through the annual TIGER/Line release. For…
DATA and TECHNOLOGY, Local Redistricting, , ,
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BBSP vs. BAS: Two Census Programs, Two Crucial Jobs

BBSP vs. BAS: Two Census Programs, Two Crucial Jobs

By EditorJun 04, 2026
The Boundary and Annexation Survey (BAS) and the Block Boundary Suggestion Project (BBSP) are often conflated; both involve local geography and the Census Bureau, but they do different jobs. BAS is the Bureau's annual survey to keep the legal boundaries and names of governments current, such as city limits, county lines, township boundaries, and tribal areas. BBSP is a once-a-decade phase of the Redistricting Data Program in which a state suggests which features the Bureau should use as statistical census tabulation block (census block) boundaries. The other differences follow from that split. BAS runs every year, and each eligible government…
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From 1990 to 2030: A Short History of the Census Block-Boundary Suggestion Project

From 1990 to 2030: A Short History of the Census Block-Boundary Suggestion Project

By EditorMay 22, 2026
The Block Boundary Suggestion Project (BBSP) is now in its fourth decade. It began as part of the Census Bureau's first nationwide Redistricting Data Program for the 1990 Census, following a 1984 pilot test that yielded positive results, which led to its full implementation. While census blocks were first used in 1940, only for cities of 50,000 or more inhabitants and other governments that contracted for the work, they were first used nationwide in 1990. Along with the nationwide census block-numbering system, which gave states the small-area geography they needed to meet Voting Rights Act obligations and minimal-population-deviation districting standards, BBSP helped move redistricting…
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Census Bureau to Release Redistricting Data on Aug. 12. Four Days Early.

Census Bureau to Release Redistricting Data on Aug. 12. Four Days Early.

By EditorAug 05, 2021
U.S. Census Bureau Press Release: August 5, 2021. The U.S. Census Bureau will hold a news conference to discuss the release of the first local level results from the 2020 Census. States use these data on race, Hispanic origin, and the voting-age population to redraw the boundaries of their congressional and state legislative districts. The news conference will provide initial analysis of the first local level results from the 2020 Census on population change, race, ethnicity, the age 18 and over population, and housing occupancy status. A live Q&A session with Census Bureau subject-matter experts will immediately follow the briefing…
Census Data and Geography, DATA and TECHNOLOGY, LATEST, NEWS, Redistricting Functions, , , ,
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Recent Census Data Developments Call into Question its Suitability for Redistricting

Recent Census Data Developments Call into Question its Suitability for Redistricting

By EditorAug 01, 2021
In the span of just a few days and just weeks before official census redistricting data is scheduled to be released, the Census Bureau reveals two rather startling revelations about the data. "Fuzzy Blocks" First, the Acting Census Director Ron Jarmin warned in the Director's Blog that the information in individual census blocks - the smallest and most detailed unit of data - will appear "fuzzy" and at times nonsensical due to the Bureau's application of privacy measures, and thus should not be used for building redistricting maps. Blocks are often used as the basic building blocks of redistricting maps…
Census Data and Geography, DATA and TECHNOLOGY, LATEST, NEWS, Redistricting, Redistricting Functions, Redistricting Prep, , , , , , ,
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Union of Concerned Scientists Release Report on 2020 Census Data Accuracy

Union of Concerned Scientists Release Report on 2020 Census Data Accuracy

By EditorJul 30, 2021
Concerns about census data accuracy have lead experts to worry about "the potential undercounting of variousgroups in the country and how undercounts might affect federal funding allocation, redistricting efforts, and representation. The Union of Concerned Scientists released this report in July describing the possible effects that undercounting may have on specific populations. From the Report: ". . . worries include potential undercounting of Hispanic populations in many communities and of young children, as well as underestimates of population at the state level (Epstein and Medina 2021; O’Hare et al. 2020; Bahrampour,Rabinowitz, and Mellnik 2021). In this report, we seek to…
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Redistricting Data: What to Expect and When

Redistricting Data: What to Expect and When

By EditorJul 28, 2021
Director's Blog - BY DR. RON JARMIN, ACTING DIRECTOR: Since releasing the apportionment results in April, we’ve had several teams working hard on the next set of 2020 Census data — the redistricting data. These data play an important role in our democracy and will begin to illuminate the changes to the local and demographic makeup of our nation over the last decade. These data include the first sub-state population counts and demographic characteristics from the census, information that states typically use for redistricting — the process of redrawing electoral district boundaries based on where their populations have increased or…
Census Data and Geography, DATA and TECHNOLOGY, NEWS, Redistricting, Redistricting Functions, Redistricting Prep, , , , , , , ,
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Resources Available to Prepare for the 2020 Census Redistricting Data Release

Resources Available to Prepare for the 2020 Census Redistricting Data Release

By EditorJul 28, 2021
Press Release- BY JAMES WHITEHORNE, CHIEF, REDISTRICTING DATA AND VOTING RIGHTS OFFICE: In a few weeks, we’ll release the 2020 Census redistricting data in our legacy summary file format. And a few weeks after that, we’ll release the same data in an easier-to-use format. We’re releasing the same data twice but in different formats at different times to make sure states get the data as quickly as possible. Acting Director Dr. Ron Jarmin explained these two releases in his blog, Redistricting Data: What to Expect and When. In this blog, I provide more detail about the formats and support materials available,…
Census Data and Geography, DATA and TECHNOLOGY, LATEST, NEWS, Redistricting, Redistricting Prep, , , , , , ,
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